From 22ac3628a15737af8f59d1e3b1d38b74edc7f1b9 Mon Sep 17 00:00:00 2001 From: Dave Gauer Date: Sat, 8 May 2021 18:51:08 -0400 Subject: Fix 076, add 077,078 sentinels and many-item pointers --- exercises/078_sentinels3.zig | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 exercises/078_sentinels3.zig (limited to 'exercises/078_sentinels3.zig') diff --git a/exercises/078_sentinels3.zig b/exercises/078_sentinels3.zig new file mode 100644 index 0000000..bad4810 --- /dev/null +++ b/exercises/078_sentinels3.zig @@ -0,0 +1,27 @@ +// +// We were able to get a printable string out of a many-item +// pointer by using a slice to assert a specific length. +// +// But can we ever GO BACK to a sentinel-terminated pointer +// after we've "lost" the sentinel in a coercion? +// +// Yes, we can. Zig's @ptrCast() builtin can do this. Check out +// the signature: +// +// @ptrCast(comptime DestType: type, value: anytype) DestType +// +// See if you can use it to solve the same many-item pointer +// problem, but without needing a length! +// +const print = @import("std").debug.print; + +pub fn main() void { + // Again, we've coerced the sentinel-terminated string to a + // many-item pointer, which has no length or sentinel. + const data: [*]const u8 = "Weird Data!"; + + // Please cast 'data' to 'printable': + const printable: [*:0]const u8 = ???; + + print("{s}\n", .{printable}); +} -- cgit v1.2.3-ZIG